Effect of Crosslinking Agent and Blowing Agent on the Properties of Natural rubber: Morphology and Mechanical Properties - Before and After Fuel Swelling
Keywords:Natural rubber, Swelling, Crosslinking agent, Blowing agent, Porous
This research work studies the effect of crosslinking agent and blowing agent at various concentrations, on morphology and mechanical properties, as before and after fuel swelling, of the natural rubbers which applied as the self-sealing layer of the fuel tank. The rubbers were blended with the crosslinking agent (0.5 and 1.5 phr), and the blowing agent (0, 4, 8 and 12 phr) at various concentrations, by using a two-roll mill machine. The curing time (tc90) of each rubber was measured by using an oscillating disk rheometer. The rubbers were fabricated by using a hot-press compression molding machine. Then, the rubbers were measured the porous content and the mechanical properties (such as ultimate tensile strength, elongation at break and modulus), as before and after fuel swelling, by using an optical microscope and a universal testing machine, respectively. It was found that the crosslinking agent and the blowing agent affected to morphology and mechanical properties of the rubbers, as before and after fuel swelling. From these results, it can be concluded that the best formula that proper to use as self-sealing materials was NR2, which was the rubber that blended with the crosslinking agent and the blowing agent at 1.5 and 4 phr, respectively. Because this rubber has a proper ratio of the rubber matrix and the porous, as a result, it has the highest rate of swelling and strength, as before and after fuel swelling.
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